Idiopathic cervical dystonia is the most common form of focal dystonia in adults.^1,2 It is characterised by involuntary, sustained contractions of the cervical muscles and produces abnormal head movements or postures. Although deep brain stimulation (DBS) of the globus pallidus internus (GPi) is now accepted in the treatment of a wide spectrum of dystonias including cervical dystonia (for a review, see Krauss³), the mechanisms underlying its beneficial effects on dystonia remain unclear. We report a patient in whom continuous long term (22 month) bilateral pallidal stimulation eventually produced stimulation independent relief of cervical dystonia.

This 54 year old right handed man had a one year history of involuntary head rotation toward the left. He had no previous exposure to neuroleptics and no family history of dystonia. On admission in June 2000, he manifested severe cervical dystonia with neck pain characterised by left and posterior head turn and tilt (fig 1A). The right sternocleidomastoid muscle was contracted and hypertrophied. His cervical dystonia decreased in the supine position or when performing a sensory trick which consisted of putting his right hand on his chin or neck. On the Toronto western spasmodic torticollis rating scale (TWSTRS), his total severity score (TSS) was 25 (maximum = 35), and his total disability score (TDS) was 21 (maximum = 30).